Bioprocess monitoring: An optical biosensor for rapid bioproduct analysis

The use of an optical biosensor for rapid bioproduct analysis is described. The biosensor, which is sensitive to changes in the concentration of biopr oduct at its biologically active surface, has been shown to provide concent ration data within 10 s of sample addition to the device. This has been ach ieved through the use of linear regression analysis to extract information from the early part of the biosensor interaction profiles. The system has b een used to monitor both the production and purification of antibody fragme nts expressed during batch fermentation of recombinant Escherichia coli. Da ta obtained using the biosensor have been used to provide real-time profile s describing the location of antibody fragments during bioprocessing. Biose nsor data have also been compared with those obtained from ELISA, the tradi tional method of retrospective analyses of samples collected during bioproc essing. (C) 1998 Elsevier Science B.V. All rights reserved.